Ye

					  Intra-Carrier Solutions
Enabled by the OIF NNI

                   Erning Ye
            Nortel Networks
                                           Reference Network
                            Metro                                     Metro
                                                      E-NNI
                                   E-NNI
EMS

        Regional                           Regional


              E-NNI


                                     E-NNI            I-NNI   Core
                                                                         UNI


      UNI                                                     E-NNI
                    Core
                           E-NNI
                                                                         Metro
                                                  Regional
      EMS


            Metro
                           Multiple Control Domains
   Each domain could be a core, regional, or metro network.
    The control inside each domain is independent:
     • Different signaling control systems (e.g., proxy) with
       different protocols (e.g., PNNI, CR-LDP, RSVP, etc.)
     • Different routing control systems (e.g., centralized or
       distributed) with different protocols (e.g., PNNI, OSPF, IS-IS,
       etc.)
     • Different protection and restoration mechanisms.
     • Different EMS/NMS
     • Use UNI or NMI to initialize and/or terminate connection
       services.
     • Different addressing scheme and/or space inside domain.
   Implementation agreement on E-NNI between domains
    provides end-to-end services that are transparent to users.
Sub-network Organization and Routing Areas




                                                          Sub-network

                                           RA.2                 RA.1
                        Sub-network

                                                        E-NNI
                                  E-NNI
             RA.2.2                       Sub-network
            Sub-network                     RA.2.1
                                                                Sub-network
                       RA.2.2.2
       RA.2.2.1
                                                                  RA.top
                  RA.2.2.3
                   NNI Routing – Requirements
   Accept ITU-T G.7715 routing requirements,
    architecture and terminology.
   Scope of routing area is a consequence of sub-
    network organization that is described in G.805 at a
    given layer.
   Subdivision of the network into routing areas where
    the areas can contain smaller areas. This creates
    routing levels.
   4 levels of routing hierarchy is required by carriers
    (OIF NNI requirement).
   Interoperability between adjacent routing areas is
    domain-domain routing protocol based on a
    hierarchical link state protocol.
                                       Sub-network Abstraction
                                         and Routing Controller
   Abstracted
intra-domain link


                                        RA.2.2




                      RC
                                                                    RC
                                                                                  RA.2.2.3
                                                                                       RC


                                                                    RC
               RA.2.2.1                            RC



        Abstract TE links                                                Abstract TE links
        Centralized routing control                                      Distributed routing control
                                        RA.2.2.2

                                      Abstract node
                                      Centralized routing control
                                           NNI Routing
   Separation of transport plane and control plane:
    •   Separated address space for routing controller and
        transport nodes
    •   Separated topology for routing controller and
        transport nodes
   Routing control could be centralized or distributed.
   Transport sub-network could be abstracted to be
    one node or several border nodes with abstract
    intra-domain links.
   Transport routing’s main function is to provide path
    computation to Connection Management (Control
    plane). In hierarchical routing, the path is
    computed at certain routing level.
                                                                        NNI Signaling
                          Network Call Controller

                                            Connection Controller

                       Domain A                 Domain B                       Domain C

             UNI                      E-NNI                         E-NNI                   UNI
    Client                                                                                            Client


                                               SPC Service

                                                    SC Service

  Call
Segment
               UNI     Sub-network     NNI          Sub-network       NNI     Sub-network     UNI
             Segment     Segment     Segment          Segment       Segment     Segment     Segment
                                    Call/Connection
                       Separation and Call Segments

   Call model is part of ASON architecture (G.8080), G7713 and
    OIF NNI.
   In a multiple control domain environment, the end-to-end call
    is achieved by concatenating multiple individual UNI, sub-
    network and NNI call segments.
   Each call segment could have multiple connections
    associated with it (e.g., 1+1 path protection, virtual
    concatenate connections).
   Network call controllers and connection controllers are
    defined in G.8080 and used in the NNI signaling specification.
     • NNI call controller is responsible for associating the call
        segments of NNI and sub-network
     • NNI connection controller is responsible for signaling
        protocol interoperability
      NNI Application – Domain Based Recovery

   Call/connection separation and call segmentation by ENNI
    enables domain based protection and restoration
   ENNI can be used to separate rerouting (recovery) domain.
    Each rerouting domain contains one or more than one call
    segment (A rerouting domain may contain other rerouting
    domains).
   Each rerouting domain could have its own protection
    mechanism, e.g., liner protection on ENNI link, APS protection
    inside one domain, and 1+1 path protection in another
    domain.
   The call controller at ingress ENNI performs redial function in
    the scope of rerouting domain.
   The failure happens in one domain would not cause
    connection teardown in other domains.
                   Recovery Example



Client
                   X
                                        Client

           E-NNI             E-NNI




Client
                       X
                                     Client

         E-NNI             E-NNI

				
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